Middle English prolongenfrom Old French prolonguerfrom Late Latin prōlongāre Latin prō-forthpro–1 Latin longuslongdel-1 in Indo-European roots
American Heritage Dictionary of the English Language, 5th Edition
Prolong Sentence Examples
He quickened his pace, having little reason to prolong the trip.
Though his recovery was rapid and complete, he did not choose to prolong his stay abroad.
To prolong the life of your hair trimmers, you will need to clean them regularly.
When Leopold I., duke of Austria, took Richard prisoner and delivered him to the emperor, Philip did his utmost by offers of money to prolong his captivity, and, allied with the English king's brother.
Not only will this save energy, it will prolong the life of your clothes.